Research Grant Programs
The R-series includes the most common research grant programs such as NIH's main independent research project grants (R01), small grants (R03), research enhancement awards (REA, R15), exploratory and developmental research projects (R21), clinical trial planning grants (R34), high priority short-term projects (R56), and more.
Single grant that funds at least two related research projects collaborating for a common goal. Multiproject applications may be investigator-initiated or may respond to a solicited funding opportunity announcement.
This page discusses the NIH standard independent R01 grant as well as the potential benefits and drawbacks of the small grant (R03) and exploratory/developmental research grant (R21).
A program officer in your area of science can give you application advice, NIAID's perspective on your research, and confirmation that NIAID will accept your application.
Find contacts and instructions at When to Contact a NIAID Program Officer.